1. Field of the Invention
The invention relates to a map-information providing system for providing map information required by a user through a computer network.
2. Described of the Related Art
In recent years, information providing services with the aid of computer networks such as the Internet, an intracompany network system (an intranet) have been explosively expanded as information terminals such as a microcomputer have achieved widespread use.
Such information providing services include a map-information providing service for providing map data required by a user to an information terminal via the computer network.
With the map-information providing service, when a user enter information for designating an address, a name of a facility and/or the like into the information terminal, a database server retrieves a map image corresponding to the designated information entered by the user from a map database which is stored with data of map images in advance, and then provides the data file of the retrieved map image to the user's information terminal via the computer network such as the Internet.
Such map-information providing service is available, for example, when a WWW (World Wide Web) page of a corporation or the like displays a map showing locations of sales offices or the like of the corporation in response to the request of the user.
FIG. 5 shows a conventional map-information providing system through the Internet for offering the aforementioned map-information providing service.
In FIG. 5, reference symbol S1′ is a map-information providing site managed by a corporation or the like which provides map information to a user. Reference symbol S2′ is a map database site for collectively offering the providing service of the map information.
The map-information providing site S1′ and the map database site S2′ are connected to an internet I. An information terminal T is connected to the map information providing site S1′ and the map database site S2′ by means of connecting to the internet I through the public switched phone network and an access server which are not shown.
The map-information providing site S1′ is provided with a WWW server S1a′ for displaying a web page to provide map information to the user information terminal T, and a position information database S1b′ storing position data representing coordinates (a latitude and a longitude) on a map corresponding to an address, a name of a facility, a telephone number or the like.
The map database site S2′ is provided with a map server S2a′ for retrieving map images to provide the data file of the retrieved map image to the information terminal T, a map-information database S2b′ storing map image data, and a retrieval database S2c′ storing retrieval data representing the correspondence between the map image data stored in the map-information database S2b′ and the position data representing the coordinates on the map.
The information terminal T is a user terminal, which uses an application program referred as a WWW browser so as to receive services of the WWW.
In the above map-information providing system, a user designates the URL (Uniform Resource Locator) for connecting from the information terminal T to the map-information providing site S1′ via the internet I, and then input the designation information, e.g. an address or a name of a facility, on the displayed web page to see the required map image. Thereupon, the WWW server S1a′ of the map-information providing site S1′ compares a character string of the entered address or the like with the position database S1b′. The corresponding position data is read out and sent to the information terminal T.
The position data is sent from the information terminal T to the map database site S2′.
The map server S2a′ of the map database site S2′ compares the sent position data with the retrieval database S2c′. The corresponding map image data is read out from the map-information database S2b′, and the read-out data file is sent to the information terminal T to display the map image thereon.
The map-information providing system is in no need of storing enormous amounts of map data in particular map-information providing sites S1′ because the map database site S2′ collectively manages the map image data, and thus the map-information providing system has a feature that the burdens on a corporation or the like who manages the map-information providing site S1′ are significantly reduced.
However, with the aforementioned conventional map-information providing system, for example, when a corporation or the like managing a map-information providing site S1′ opens its new shop or relocates its existing shop, the need for providing map information in accordance with the new position data arises. In this event, the corporation must update the position information database S1b′ of the map-information providing site S1′ as occasion demands. In consequence, there is a disadvantage that the corporation or the like managing the map-information providing site S1′ bears the significant burden of the updating operation.